The purpose of this study is to establish anthropometric parameters for assessing normal growth of Aotus monkeys in captivity, to assess alterations in the development of experimentally treated animals, and to provide an age estimation for primates with unknown birth dates. The anthropometric and dental data collections were made on a regular basis until the animals reached maturity. The anthrometric measurements entailed, head length, head breadth, crown-rump length, foot length, hand length, bitrochanteric diameter and overall length. Thus far it has been determined that weights at six months were between 402 and 563 grams, approximately half that of the adults. Deciduous tooth eruption patterns are similar to other nonhuman primates. It has been observed that the growth rate plateaus at one year and six months of age. The anthropometric measurement correlating most closely with increasing age is the bitrochanteric diameter.